Condensate pump and control means



Apr i195@ F. N. znMMERn/AANN ET AL 2,8295@ CONDENSATE: PUMP AND CONTROL MEANS Filed Aug. 25. 1956 2 Sheets--Sheefrl l Am 89 3958 F. N. ZHMMERMANN HAL 2,82%,59

CONDENSATE PUMP AND CONTROL MEANS Filed Aug. 25, 1956 2 Sheets-.Sheei'l 2 EN? [il i e784 1 9@ 74 n 1 ll/ 11x WMU f.' Z/Mvf/WN- INVENTOR5,

United States Patent C i GCNDENSA'TE PUMP AND CONTROL MEANS Frederick N. Zimmermann and Willy E. Zimmermann, Chicago, ill., assignors to March Manufacturing Co., Simi-ile, lili., a corporation of Illinois Application August 23, 1956, Serial No. 605,747

t claims. (ci. s-26) The present invention pertains to a novel pump and control means designed particularly for draining purposes, but also capable of service for the general purposes of elevating water and other liquids.

It is among the objects of this invention to provide an electrically driven pump with electric motor and the hydraulic pumping elements embraced in the same housing, and with lloat control mechanism enclosed in an enclosure secured to the exterior of said housing, the lower portion of the housing and the control float constructed in such a manner that they can be submerged in water such as found in a drip pan beneath an air conditioning apparatus, whereby the pump will run for periods of time at high efficiency, without trouble or care until the drip pan, or the like, is substantially dry.

With the condensate pumps of earlier inventions the pump housings are partially submerged under water in a drip pan beneath an air conditioning apparatus, and they run continuously; when there is water in the pan, or when the pan is substantially dry. The pumps of said early design will continue to run at their normal speed twenty-four hours a day, or until manually stopped. Thus, .it will be seen that said pumps function for hours when it is not necessary, since an average pump will maintain a drip pan substantially dry `seventy percent of the time. lt is well known that pumps which do not run continuously will last for a greater period of time without repair.

Another object of the invention is to provide a pumping unit comprising motor, pump and oat `control in which the parts are closely coupled and in lwhich the whole of the instrumentality is of low height and small mass, whereby it will tit conveniently into very tight drip pan locations and providing adjustable legs for positioning in drip pans having an irregular shape and angularly arranged floors.

Another object of the invention is to provide a pump construction and method of pumping water and other liquids, wherewith both the driving motor and pump impeller may be correctly centered invertical alignment within the pump housing of lightweight casting and wherewith the impeller may be properly borne and suspended within the pump chamber and supported both axially and radially with such accuracy by the casting of the housing to obviate outboard bearings, universal joints or loose couplings between the motor and impeller.

Another object of the invention is to provide a pump of the class described with a more efficient seal for preventing 'iiuid being pumped and/ or from sleeping into the motor chamber.

Another object of this invention is to provide a condensate-removal pump embodying: a pump housing; said housing having intermediate the upper end and the lower end thereof a transversely extending apertured, but otherwise imperforated, internal partition; said partition dividing the inte-rior of said housing into a pump chamber on one side thereof and a motor chamber on the other side thereof; said pump chamber embodyingv 2,829,598 Patented Apr. 8, 1958 an impeller cavity, an inlet and a discharge outlet for liquid being pumped thereby; a motor mounted in said motor chamber and having its shaft extending through the aperture in said partition and into said pump charnber; a sealing means surrounding said shaft, sealing said pump chamber from said motor chamber; said shaft lhaving an impeller secured to the lower end thereof; said impeller rotatable about a vertical axis within said impeller cavity; a circular channel located within said partition at a distance from and completely encircling said aperture; a plurality of air-bleed passages suitably located and larranged Within `said partition, each connecting said circular channel with said impeller cavity; a manifold-type channel arranged within said partition connecting said circular channel with the exterior of said pump housing; said channels and passages thereby connecting said impeller cavity with the exterior of said housing, allowing entrapped air within said impeller chamber to escape, thereby preventing an air lock within the pumping chamber; said motor in the motor chamber being controlled to operate intermittently by a float mechanism attached to the exterior of said pump housing.

Another object of the present invention is to provide a rotary pump handling a substantial volume of water and having a natural tendency to create a circular motion of the body of water in which the pump is partially submerged, mixing Iair with water, and including air-bleed passageways to eiectively prevent, check, or relieve air locks within the enti-re impeller cavity. By the present invention, air-bleed passageways are provided within a partition separating the interior of the pump housing into an impeller cavity on one side thereof and a motor chamber on the other side thereof; the small air-bleed passageways and larger channels forming a manifoldtype channel between the low pressure areas of the impeller cavity and the exterior of the pump housing, which effectively relieves, checks, or prevents the formation of an air lock within the impeller cavity.

Accordingly, a primary object of this invention is to provide a novel condensate pump free of any air locks and with a control float means; all arranged and adapted to run intermittently as desired to empty a sump, a drip pan, or the like, to substantial dryness.

Another object of the invention is to provide a novel condensate pump and float control means including novel means for preventing an air lock in a pump without the necessity of sacriiicing pump output and efficiency.

Another object of the present invention is to provide a method of making and assembling a pump for carrying out some, or all, of the preceding objects `and more particularly to providea method of locating a `planetary airbleed system, locating and aligning the motor and impeller parts of a pump with res ect to their respective working. chambers and coating parts, housing, ilo-at mechanism and instrumentalities.

Other objects include providing method and means for making an eflicient, compact, longlived, rugged rotary pump economically and effectively.

Other objects and features of the invention will be set forth more fully hereinafter.

The full nature of the invention will be understood from the accompanying drawings and the following description and claims.

`In the drawings:

Figure l is a fragmentary View in elevation partially broken away and in section, `illustrating the condensate pumping unit and control means of this invention in operative relation to a drip pan beneath an evaporator, or an air conditioning apparatus, from which liquid is to be pumped whenever it accumulates;

Figure 2. is an end view of the condensate pumping ice senses unit shown in Figure 1, with parts broken away and parts shown in section;

Figure 3 is a top plan view of the condensate pump shown in Figures l and 2, with parts broken away;

Figure 4 is a side elevational view of the pump shown in Figures 1, 2 and 3, with parts broken away and parts shown in section;

Figure 5 is a fragmentary bottom plan View of the pumping unit shown in Figure 4, showing the impeller assembled within the impeller cavity;

Figure 6 is a view similar to Figure 2 with the tloat and switch mechanism shown in raised position.

Referring to the drawings, the reference numeral 10 designates a suitable, conventionally illustrated drip pan, or reservoir, or the like, beneath the evaporator 11, in which a quantity ol liquid 12 will be collected; said liquid to be removed from the drip pan 10 by the condensate pump, or unit, 14 when partially immersed in said liquid.

Referring to Figures 2, 3, 4, 5 and 6, wherein details of the construction of the pumping unit 14 are illustrated, the pumping unit consists of a pump housing 15 constructed from a suitable casting embodying a base portion 16, suitable side walls, and end walls 17 and 18. The housing 15 having intermediate the upper portion and the lower portion thereof a transversely extending wall 2t), said wall 2t) provided with a cent-ral opening 21, otherwise not imperforated, and said wall dividing the interior of said housing 15 into a motor chamber 22 and a pump chamber 23. is closed by a bottom plate 24 to form the impeller cavity. Said plate 24 is provided with a central opening 26 for the entry of liquid 12 into the impeller cavity 23. In the end wall 18, adjacent the base portion 16, is provided an enlarged boss member 27, said member 27 being bored out to form an interior opening 28 leading into the impeller cavity 23, and forming an exterior opening 29. The opening 29 is provided with threads to receive a pipe fitting 30 adapted to retain a suitable hose, iron pipe, or copper tubing 31. Attached to said housing 15 is a metallic U-shaped member 25 which forms an enclosure for the pump oat control mechanism. The upper portions of said housing 15 and said metallic member 25 are covered by a top metallic cover 32 secured to the housing 15 and member 25 by self-tapping screws 33. The lower portion of said housing 15 is formed with two legs 34. Said legs 34 and tl e outer corners of the base portion 16 are provided with adjustable bolts 39, the heads of said bolts 39 supporting the entire pump 14 in the drip pan 1G; said bolt heads thereby elevating the bottom plate 24 a desired distance above the bottom of said drip pan 10.

Referring to Figure 4, the motor chamber 22 is shown enclosing a motor 35 having a rotor 36 rotatable on a Vertical axis and driving a shaft 37. It will be noted that the motor has the eld 38 mounted to one side of the rotor 36. Said partition 20, provided with opening 21, is further cored out to form a grommet cavity 4t) to retain a grommet 41. The motor thrust bearing 42 is mounted upon said grommet, whereby it supports said rotor 36; said shaft 37 being rotatably mounted in said grommet. The impeller 43, attached to the lower end of said shaft 37 and driven thereby, is disposed in the impeller cavity 23. Said grommet 41 permits the shaft 37 to pass from said motor chamber 22 downwardly into said impeller cavity 23 and to rotate freely, and further seals the motor chamber from the pump chamber, preventing any liquid from entering said motor chamber.

Referring particularly to Figures 4 and 5, it will be observed that the partition Ztl is provided with four small vertical air-bleed passageways 46, 47, 48 and 49; a circular channel 5l) located below said grommet cavity and within the upper surface of said partition at a distance from and completely encircling the circular Said pump chamber 23 opening 21 adapted to receive the shaft 37; and a larger horizontal air-bleed channel 51. Said passageways 46, 47, 48 and 49 extend downwardly `from the base of the circular channel 50 to the upper wall of said impeller cavity 23. Said horizontal channel 51 extends from an opening 52 in the outside of said pump housing 15 through said partition 20 to said circular channel 50. The grommet 41, which is held downwardly by said bearing 42, seals the circular channel 50. It will be observed that a continuous passageway is provided for a small quantity of air, and/or water, or both, to pass from the upper portion of the impeller cavity to the outside of said housing 15. Said electric motor 35 is supplied by electric current supplied through power cables 55 and 56, shown by Figures l and 5.

From the above, it will be seen that this invention provides an electric pump 14 which can be partially submerged in water in a drip pan 10 for pumping said water 12 to a sewer or to a roof or other desirable place in a building. The motor 35 and pump impeller 43 are correctly centered in vertical alignment within the pump housing 15. The pump 14 is designed for handling a volume of water, drawing the liquid through the central opening 26, said impeller 43 forcing the liquid through opening 28 for disposal through the tubing 31. Said impeller 43 also forces air and a small quantity of water 12 outwardly through the small vertical passageways 46, 47, 48 and 49, through the circular channel 50 and larger channel 51, said water drawing any air remaining in the impeller cavity to the outside of said housing. lt is clearly seen that said passageways 46, 47, 48, 49, the circular channel 50 and channel 51 form a continuous manifold-type channel between the low pressure areas in the impeller cavity 25 to the exterior of the housing 15, which checks and prevents the formation of an air lock within the pump chamber, and/ or impeller cavity.

In assembling a pump of the above-described type, the grommet 41 is placed in the counter bore 40, the motor is placed within the pump housing and secured to the base 40 by suitable studs; special attention being given to sce that shaft 37 turns freely in bearings 42 and grommet 41; the impeller is then placed upon the free lower end of shaft 37 and soldered in place; and the bottom plate 24 and a gasket 63 are then placed upon the base portion 16 enclosing the impeller cavity 23.

The pump control unit enclosed within said U-shaped member 25 is mounted upon a C-shaped hanger bracket 70, the vertical wall 71 thereof being secured to the exterior of wall 17 of said housing 15 by machine screws 73 and 74. The lower horizontal arm portion 75 of said bracket is formed with an aperture 76 near its outer end, the arrangement being such that a vertical lloat rod 77 attached to a lloat 78 may pass freely therethrough. The upper horizontal portion 90 of said bracket 70 is formed with an aperture 91 near its outer end, said aperture 91 being directly -above said aperture 76 in said arm portion 75. Said horizontal portion arm 90 is not constructed as wide as said horizontal arm portion 75, thereby leaving an upper ledge portion 92 upon said bracket 70. Carried upon the upper ledge 92 of said bracket 70 is a terminal board 80 secured thereto by self-tapping metal screws 81 and 82. Extending outwardly from said bracket 70 is boss 84 to which is pivotally mounted an arm 85 by means of a pivot 86 screwed into said boss. Said arm 85 s composed of a vertical body portion 87, an intermediate extending vertical arm portion 88 and a horizontal free end portion 89, said free end 89 having an aperture therein to allow said float rod 77 to pass freely therethrough. The intermediate arm portion 88 is provided with a clip 96 to carry a mercury switch 98.

The float 78 is generally a hollow metal oat with a vertical guide rod 77 suitably secured to the upper portion thereof. vIntermediate the ends of said rod 77 are properly spaced two retaining rings, a lower ring 99 and an upper ring 100. Said rings may be referred to as lloat stops genaues secured to said oat rod 77, whereby the free end 89 of arm 85 alternately engages said rings during the travel of said rod upwardly and downwardly. The float 78 is intended to ride upon the surface of the liquid body of Water in the drip pan 10. In the normal lower portion of the oat, as shown by Figure 2, the mercury switch is arranged to be in open position. As soon as the liquid level in the drip pan rises above the specified height, the float 78 rises with such liquid and the rod 7'7 moves upwardly causing ring 99 to engage the free end 89 of arm 85, said arm will tilt about the pivot 86 causing the mercury in the switch to close the contacts and the motor circuit, thus establishing pump operation. When the float rod 77 drops due to lowering of the float, the ring ltiti contacts the upper surface of arm end S9, tilting said arm 85 downwardly, causing the mercury to open the contacts and the motor circuit. In this way the action is automatic, the float and the mercury switch closing and alternately opening the circuit to the motor 35 and as a consequence maintaining a substantially dry condition in the drip pan. The electric current circuit is clearly shown by Figures 3 and 4, line MP6 is secured to the terminal block by screw 107 where it is joined by line 56 connected to the motor; line 10S is secured to the terminal block by screw 109 where it is joined by line 110 connected to the mercury switch; return line 111 leading from the mercury switch is secured to the terminal block by screw 112 where it is joined by line 55 connected to the motor. The pump housing and float control chamber are protected by a removable cover 32 heldin place removably by screws 33. The pump chamber is closed except for openings 26 and 28. Water enters the pump chamber 23 through opening 26 and is forced outwardly through the opening 28. The float control chamber is entirely open at its lower portion so that the lloat is free to drop to substantially drip pan floor level when placed therein. In assembling the float control mechanism, the oat rod '77 is inserted from the base of the unit, said rod is passed through aperture '76 in arm 7S, ring 99 is placed upon said rod 77, said rod is then passed through aperture 95 in extension 89, ring 100 is then placed upon said rod 77,

and the upper end of said rod 77 is passed through aperture 91 in bracket extension 90; the proper positioning of rings 99 and 100 regulates the proper functioning of ysaid mercury switch and in turn the proper operation of the pump.

The terms and expressions which have been herein employed are used as terms of description and not limitation, and there is no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described. It is recognized that various modifications are possible within the scope of the invention claimed.

Having thus described this invention, what we claim as new and desired to secure by Letters Patent of the United States is:

l. A portable electric condensate pump, comprising: a supporting housing having a pumping chamber and a motor chamber therein; said pumping chamber provided with a liquid inlet and a liquid outlet; the base portion of said housing adapted to be immersed, at least in part, in a supply of liquid to be pumped; a motor supported within said motor chamber for driving a vertical impeller shaft extending downwardly therefrom and extending into said pumping chamber; an impeller mounted on the lower end of said shaft and rotatable therewith in said pumping chamber; a reservoir type structure adjacent to said housing and supported thereby, open at its lower end and closed at its upper end; `a supporting bracket attached to the exterior of said housing and confined within said reservoir; a oat and guide rod within said reservoir, the movement of said oat and rod governed by openings in said bracket; a normally open mercury switch pivotally connected by means of an arm to said bracket; said switch combined with a circuit connected with said motor; said mercury switch closed automatically when the oat raises incident to rising liquid level in the reservoir for controlling the action of said motor and impeller driving means.

2. A portable electric condensate pump, comprising: a supporting housing having a pumping chamber and a motor chamber therein; said pumping chamber provided with a liquid inlet and a liquid outlet; the base portion of said housing adapted to be immersed, at least in part, in a supply of liquid to be pumped; a motor supported within said motor chamber for driving a vertical impeller shaft extending downwardly therefrom and extending into said pumping chamber; an impeller mounted on the lower end of said shaft and rotatable therewith in said pumping chamber; a reservoir adjacent said housing and enclosed by said walls, said walls supported by said housing, said reservoir open at its lower end and substantially closed at its upper end; a supporting bracket attached to the exterior of said pump housing `adjacent said reservoir and confined within said reservoir; a movable float in said reservoir; a float guide rod connected to said float extending upwardly through openings in said bracket; a circuit having a normally open mercury switch connected to said motor; said switch pivotally connected by means of an arm to said bracket; said switch closed automatically when the float raises incident to rising liquid in the reservoir for controlling the action of said motor and impeller driving means, and said switch opening automatically when the float lowers incident to declining liquid level in the reservoir.

3. A portable electric condensate pump, comprising: a supporting housing having a pumping chamber and a motor chamber therein; said pumping chamber provided with a liquid inlet and a liquid outlet; the base portion of said housing adapted to be immersed, Iat least in part, in a supply of Iliquid to be pumped; a motor supported within said motor chamber for driving a vertical impeller shaft extending downwardly therefrom and extending into said pumping chamber; an impeller mounted on the lower end of said shaft and rotatable therewith in said pumping chamber; a reservoir adjacent said housing and enclosed by side walls, said walls supported by said housing, said reservoir open at its lower end and substantially closed its upper end; a supporting bracket attached to the exterior of said pump housing adjacent said reservoir and confined within said reservoir; a movable oat and guide rod secured thereto in said reservoir, said guide rod extending upwardly through openings in said bracket; a circuit having a normally open switch connected to said motor; said switch supported by an arm pivotally connected to said bracket; means upon said rod for controlling the action of said arm; said switch closed automatically when the float and rod are elevated incident to rising liquid in the reservoir as said rod elevates said arm supporting said switch; and said switch opening when the oat lowers incident to declining liquid :level in the reservoir.

4. A portable electric condensate pump, comprising: a supporting housing having a pumping chamber and a motor chamber therein; said pumping chamber provided with a liquid inlet and a liquid outlet; the base portion of said housing adapted to be immersed, `at: least in part, in a supply of liquid to be pumped; a motor supported within said motor chamber for driving a vertical impeller shaft extending downwardly therefrom and extending into said pumping chamber; an impeller mounted on the lower end of said shaft and rotatable therewith in said pumping chamber; said pumping chamber having an upper wall; a manifold-type `air-bleed passage arranged within said upper wall; the proximal end of said air-bleed passage in communication with said pumping chamber; the distal end of said air-bleed passage open to the atmosphere, allowing entrapped air within the assassin pumping chamber to escape; a reservoir adjacent said housing and enclosed by side walls, said walls supported by said housing, said reservoir open at its lower end and substantially closed at its upper end; a supporting bracket attached to the exterior of said pump housing adjacent Said reservoir and being conned within said reservoir; a movable float and associated guide rod in said reser- Voir; said guide rod extending upwardly through opening in said bracket; a circuit embodying a normally open switch connected to said motor; said switch supported by,

an arm pivotally connected to said bracket; means upon said rod for controlling the action of said arm; said switch closed when said iloat and said rod are elevated incident to rising liquid in the reservoir as said rod elevates one end or" said arm supporting said switch; and said switch opening when the tloat and rod lower incident to declining level of liquid in the reservior.

5. A portable electric condensate pump, comprising: a housing having a pumping chamber and a motor chamber therein; said pumping chamber provided with a liquid inlet and a` liquid outlet; a motor supported within said motor chamber for driving a vertical impeller shaft extending downwardly therefrom and extending into said pump chamber; an impel'ler mounted on the lower end of said shaft and rotatable therewith in said pumping chamber; the base portion of said housing adapted to be immersed in liquid to be pumped; a plurality of air-bleed passageways arranged in the walls of said pumping chamber to allow entrapped air within the pumping chamber to escape; the proximal ends of said air-bleed passageways in communication with the pumping chamber; the distal ends of said air-bleed passageways open to the atmosphere; 'a reservoir adjacent said housing, said reservoir open at `its lower end and substantially closed at the upper end; a bracket attached to the exterior of said pump housing adjacent said reservoir and coniined within said reservoir; a movable iloat with a vertical rod secured thereto arranged with said bracket, said rod extending through openings in said bracket; stop means assembled upon said rod for supporting and controlling movement thereof; a circuit embodying a normally open switch connected to said motor; said switch supported by an arm pivotally connected to said bracket; said switch becoming closed when said oat and rod are elevated incident to rising liquid in said reservoir and surrounding the base of said housing as said rod elevates one end of said 'arm supporting said switch; and said switch again becoming open when the oat and rod lower incident to the declining level of liquid around said housmg.

6, ln a device of the kind described for use with a drip pan for collecting and holding a body of liquid; a portable pump for discharging liguid from any drip pan in order to obtain ya substantially dry condition within said pan; said pump comprising a housing having a pumping chamber and a motor chamber therein; a reservoir adjacent said housing, said reservoir open at its lower end; a motor supported within said motor chamber for driving a vertical impeller shaft extending downwardly therefrom and extending into said pump chamber; an impeller mounted on the lower end of said shaft and rotatable therewith in said pumping chamber; a C-shaped bracket attached to the exterior of said pump housing adjacent said reservoir and conned within said reservoir; a movable float and supporting rod arranged with the horizontal portions of said bracket, said rod extending through openings in the horizontal portions of said bracket; stop means assembled upon said rod for supporting and controlling movement thereof; a circuit embodying a normally open mercury switch connected to said motor; said Switch supported by an arm-type lever pivotally connected to said bracket; one end of said arm-type lever and said switch being moved upwardly to close the switch when said float and rod are elevated incident to rising Iliquid in said reservoir and surrounding the base of said housing; and said switch again becoming open when the tloat and rod lower incident to the declining level of liquid around said housing.

lietierences Cited in the le of this patent UNITED STATES PATENTS 1,220,954 Chapman Mar. 27, 1917 1,804,846 Stewart May 12, 1931 1,812,874 Hedglon July 7, 1931 1,960,389 McFerran May 29, 1934 2,326,360 Ingersoll Aug. 10, 1943 2,418,221 Curtis Apr. 1, 1947 2,589,089 Johnson Mar. 11, 1952 2,669,934 Lovett Feb. 23, 1954 2,748,220 Lung May 29, 1956 2,752,461 Euler .lune 26, 1956 2,766,696 Lung Oct. 16, 1956 

